Food slicer having detachably mounted disc blade



F. GRAEF May 19, 1964 FOOD SLICER HAVING DETACHABLY MOUNTED DISC BLADE Filed Aug. 29. 1960 2 Sheets-Sheet 1 INVENTOR. FERDINAND GRAfF BY h MIZL 5. W

ATTORNEY May 19, 1964 F. GRAEF 3,133,572

FOOD SLICER HAVING DETACHABLY MOUNTED DISC BLADE Filed Aug. 29. 1960 2 Sheets-Sheet 2 JNVENTOR. FERDINAND GRAEF IMZWXMMU ATTO/P/VE Y United States Patent 3,133,572 F001) SLICER HAVING DETACHABLY MOUNTED DISC BLADE Ferdinand Graef, Munich, Germany, assignor to Ritterwerk F. Ritter & Sohn, Munich-Passing, Germany Filed Aug. 29, 1960, Ser. No. 52,684 Claims priority, application Germany Sept. 8, 1959 Claims. (Cl. 146-102) The invention relates to bread and cold-meat slicers of the kind in which the hub of a circular cutting blade is located axially on a bearing bush of the slicer casing by a fixing screw co-amally engaging the casing, the entry of food particles between the blade and the bearing bush being prevented by a sliding ring disposed in a circular recess inthe blade. One known machine of this kind employs a thrust plate which is pressed against the sliding ring by the fixing screw. This arrangement for axially securing the cutting blade is disadvantageous, because the blade must be removed fairly frequently for the machine to be cleaned. In reassembling the slicer it is difiicult to set the screw so as not to press the thrust plate too tightly or too loosely against the cutting blade. Another disadvantage is that, for the sake of resilience, the known thrust plate has a corrugated surface which acts as an undesirable dirt trap. It is the object of the invention to overcome the shortcomings of the aforedescribed known type of slicer.

According to the invention, a sheetsteel clamping disc is placed between the hub and the fixing-screw head, the

disc and screw head corresponding in diameter to the recess in the cutting blade. On the side adjacent to the screw head resilient projections project from the disc and bear against the screw head, while the opposite side of the clamping disc provides a bearing surface for a sliding ring or washer. The omission of the thrust plate and its replacement, inter alia, by the enlarged head of the fixing screw reduces the possibility of trapping food particles. The use of a clamping disc having resilient projections permits the fixing screw to be tightened to the exact extent required to secure the cutting blade axially without unnecessarily impeding its rotation.

In a preferred embodiment of the invention, the resilient projections are semi-circular and are produced by punching. They are aligned along a circle on one face of the clamping disc. The other face of the clamping disc carries tongues formed by one-sided raised edge lips of circular apertures punched from the clamping disc. According to another feature of the invention, the accessible face of the fixing screw head which is remote from the clamping disc is formed with an eccentric recess adapted to receive the edge of a coin whereby the screw may be tightened or slackened.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is an elevational sectional view of a slicer, in accordance with the invention, the section being taken through the axis of the circular cutting blade;

FIG. 2 is a side view, partly in section, showing the fixing screw and clamping disc of the arrangement of FIG. 1;

FIG. 3 is a rear elevational view of the apparatus of FIG. 2; and

FIG. 4 is a front elevational view of the apparatus of FIG. 2.

Referring to FIG. 1, the slicer illustrated comprises a support or base plate 1 to which is bolted a machine casing 2. The casing 2 is equipped in its central part with a horizontal mounting socket 25 provided with a bearing bush 3 on the cylindrical bearing face of which a circular cutting blade 4 is mounted. The bladeA is rigidly secured to a gear wheel 5 which is arranged coaxially of the blade and engages a smaller gear wheel 7 secured to a crank shaft 6. The gear wheel 5 has a central part constituting a hub 8 for the blade 4. A radial face of the gear wheel 5 is formed with a circular recess 9 wherein is accommodated a vulcanised annular fibre shim 10. The shim 10 is in sliding engagement with a matching surface provided by an annular part 11 of the casing 2.

The mounting socket 25 is formed with a coaxial tapped bore 12 accommodating a fixing screw 13 having an enlarged substantially disc-shaped head 13. A clamping disc 16 is disposed between the inner face of the disc-shaped head 13 and a confronting end face 14 of the bush 3. A vulcanised fibre washer 15 covers a radial annular face of the gear wheel 5 opposite the disc 16 and surrounding the bush 3. As can be seen more particularly in FIGS. 2 and 3, the side of the clamping disc 16 opposite the inner face of the screw head 13' has resilient axial, circumferentially spaced projections 17, 18 formed by partly punched-out integral semi-circular parts of the disc 16. The distance between each projection 17 and the circumferentially following and preceding projections 18 are equal, but the projections 17 lie on a circle of a smaller diameter, while the projections 18 lie on a circle of a larger diameter. The projections 17, 18 bear against the bottom wall of a shallow annular groove 19 in the inner face of the fixing-screw head 13'. The disc 16 also carries tongues which project axially in a direction away from the projections 17, 18. The tongues are formed by raised lips 21 of circular apertures 20 punched out of the disc 16. When the fixing screw 13 is tightened, the lips 21 bear against the end face 14 of the bush 3 and prevent the disc 16 from rotating and from loosening the screw 13. The disc 16 is axially secured on the screw 13 by a clip 22 engaging a recess in the shank of the screw 13. The side of the screw head 13' which is remote from the disc 16 is formed with an eccentric slot 24 which will conformingly receive the edge of a coin so that the screw 13 can readily betightened or slackened.

The screw 13 is partly released in the inoperative position of the slicer shown in FIG. 1. When the screw 13 is fully tightened, the disc-shaped head 13' of the screw 13 is completely accommodated in a cup-shaped circular recess 23 in the blade 4 and in the gear wheel 5, and the circular outer face of the fixing screw head 13' is coplanarwith a surface of the blade 4. After cleaning or similar operations, the apparatus described is re-assem- .bled as follows:

Before the blade 4, and associated gear wheel 5 are positioned, the shim 10 is mounted on the gear wheel. After the gear wheel 5 has been pushed onto the bush 3, the vulcanised fibre washer 15 is introduced into the recess 23 in the blade 4 and gear wheel 5, whereafter the fixing screw 13 is screwed in. The disc 16 is retained on the face of the screw head 13' adjacent the screw shank by means of the clip 22. The resilient projections 17, 18 press the disc 16 very gently against the washer 15. When the screw 13 has been fully tightened, the lips 21 of the disc 16 engage the end .face 14 of the bush 3, so that rotation of the disc 16 is prevented and the screw 13 cannot be released accidentally. When the slicer is disassembled, the screw 13 can be turned easily by means of a coin placed in the slot 24. As the screw 13 is withdrawn, the pressure with which the projections 17, 18 engage the bottom of the groove 19 is reduced. When this pressure is completely relieved, the disc 16 is free to rotate. The clearance between the projections 17, 18 and the screw head can be chosen as required, for instance, so that the projections 17, 18 are released from the head 13' by a rotation of the screw 13 through -100".

Since the main purpose of the projections 17, 18 is to press the disc 16 gently against the ring 15, the resilient projections need not necessarily have sharp edges or corners to secure the screw head 13 against being released.

The projections may be sharp-edged but preferably have rounded edges and are slightly curved lengthwise or transversely.

Depending on the dimensional relationship between the resilient projections 17, 18 and the thickness of the washer 15, the blade 4 may be secured reliably without use of washers 15 or, the blade 4 may not be capable of being secured without a washer 15 and the shim 10. This latter feature prevents undesirable wear should the washer 15 or shim 10 be missing.

Instead of a fixing screw 13 screwed into a coaxial tapped bore in the mounting socket 25, a bayonet fastening may be used. A plate corresponding to the discshaped head of the screw 13 is secured bayonet-fashion to the socket 25 in a manner known per se by insertion in the socket and rotation through an angle of 90.

The punched-out projections 17, 18 of the clamping disc 16 leave semi-circular apertures in the disc 16, and

the straight edges of the apertures along which the projections are joined to the disc 16 extend radially outwards from the center of the screw head 13'. The normal direction of rotation of the blade 4 is such that peripheral elements of the fibre washer 15 move in a direction from the arcuate edge part of the aperture left by each projection 17, 18 towards the straight edge aolng which the projection is bent out of the disc 16.

What I claim is:

1. In a slicing machine, in combination,

(a) a bearing member having a bearing face of circular cross section about an axis, and a radial end face;

(b) cutting blade means rotatably mounted on said bearing face, said cutting blade means having an annular radial face about said end face and an axially extending wall of substantially circular cross-section defining with said end face and said annular radial face a cup-shaped recess having one open axial end and one substantially closed axial end;

() fastening member releasably secured to said hearing member and having a head portion engaged in said recess and substantially closing said open end, said head portion having an inner face spacedly opposite said end face and said annular radial face, said inner face being formed with an annular groove opposite said annular radial face, said groove having a radially extending bottom wall;

(d) a disc member interposed between said inner face and said radial faces of said bearing member and of said blade means;

(e) frictional fastening means on said disc member engaging said bearing member for opposing rotation of said disc member relative to said bearing member; and

(f) a plurality of resilient projections on said disc member and engaging said bottom wall for resiliently urging a portion of said disc against said annular face of said blade means.

2. In a machine as set forth in claim 1, said bearing face being substantially cylindrical.

3. In a machine as set forth in claim 1, said disc member being of sheet material, and said projections being integral with the disc member.

4. In a machine as set forth in claim 3, said disc member being formed with a plurality of circumferentially spaced axial openings each bounded by a straight edge and an arcuate edge, said projections respectively conforming to said openings and being joined to said disc member along said straight edge.

5. In a machine as set forth in claim 4, said straight edges being elongated in a radial direction relative to said axis.

6. In a machine as set forth in claim 4, said openings being circumferentially aligned along a plurality of coaxial circles of different diameter.

7. In a machine as set forth in claim 1, said frictional fastening means including lip means on said disc member frictionally engaging said bearing member.

8. In a machine as set forth in claim 1, said bearing member being formed with an axial bore in said radial end face thereof, and said fastening member including a shank portion releasably engaging said bore.

9. In a machine as set forth in claim 8, said disc member being formed with an aperture, said shank portion passing axially through said aperture and carrying locking means for limiting movement of said disc member on said shank portion in a direction away from said head portion.

10. In a machine as set forth in claim 1, a support, said bearing member being fixedly mounted on said support; and means on said support for actuating rotation of said blade means about said axis.

References Cited in the file of this patent UNITED STATES PATENTS 

1. IN A SLICING MACHINE, IN COMBINATION, (A) A BEARING MEMBER HAVING A BEARING FACE OF CIRCULAR CROSS SECTION ABOUT AN AXIS, AND A RADIAL END FACE; (B) CUTTING BLADE MEANS ROTATABLY MOUNTED ON SAID BEARING FACE, SAID CUTTING BLADE MEANS HAVING AN ANNULAR RADIAL FACE ABOUT SAID END FACE AND AN AXIALLY EXTENDING WALL OF SUBSTANTIALLY CIRCULAR CROSS-SECTION DEFINING WITH SAID END FACE AND SAID ANNULAR RADIAL FACE A CUP-SHAPED RECESS HAVING ONE OPEN AXIAL END AND ONE SUBSTANTIALLY CLOSED AXIAL END; (C) FASTENING MEMBER RELEASABLY SECURED TO SAID BEARING MEMBER AND HAVING A HEAD PORTION ENGAGED IN SAID RECESS AND SUBSTANTIALLY CLOSING SAID OPEN END, SAID HEAD PORTION HAVING AN INNER FACE SPACEDLY OPPOSITE SAID END FACE AND SAID ANNULAR RADIAL FACE, SAID INNER FACE BEING FORMED WITH AN ANNULAR GROOVE OPPOSITE SAID ANNULAR RADIAL FACE, SAID GROOVE HAVING A RADIALLY EXTENDING BOTTOM WALL; (D) A DISC MEMBER INTERPOSED BETWEEN SAID INNER FACE AND SAID RADIAL FACES OF SAID BEARING MEMBER AND OF SAID BLADE MEANS; (E) FRICTIONAL FASTENING MEANS ON SAID DISC MEMBER ENGAGING SAID BEARING MEMBER FOR OPPOSING ROTATION OF SAID DISC MEMBER RELATIVE TO SAID BEARING MEMBER; AND (F) A PLURALITY OF RESILIENT PROJECTIONS ON SAID DISC MEMBER AND ENGAGING SAID BOTTOM WALL FOR RESILIENTLY URGING A PORTION OF SAID DISC AGAINST SAID ANNULAR FACE OF SAID BLADE MEANS. 